Reversible aerodynamic disc and gyroscopic toy

ABSTRACT

A disc with an aerodynamically shaped concave/convex surface and an inwardly turned rim has a central portion that includes a central circular depression in at least one transverse end surface thereof. The depression has a concave bottom and a right cylindrical side wall. In one embodiment of the invention, the central portion constitutes a readily removable and invertible plug so that the central depression may be arranged to face either inwardly or outwardly of the disc. In an alternative embodiment of the invention, the central portion is made integrally with the concave/convex surface and oppositely facing central depressions are formed on both (inner and outer) transverse end surfaces thereof. The disc is adapted to be spun by twirling an elongated wand the tip of which is in an inwardly or outwardly facing central depression of the disc, the disc being supported by the wand during such twirling. With the concave surface of the disc facing downwardly, twirling of the wand causes the disc to rotate, and after the disc is turning with sufficient speed a slight push of the wand in an upward direction will cause the disc either to hover or to sail through the air depending upon the magnitude and direction of the force applied by the wand and the speed of rotation of the disc. With the concave surface of the disc facing upwardly, either by inverting the central plug as in the first embodiment or by inverting the entire disc as in the second embodiment, a gyroscopic toy is provided. With the disc rotating and with its concave surface facing upwardly, the lower end of the wand the tip of which now is in the outwardly and downward facing depression can be placed on a flat surface where it will remain erect with the disc spinning on its upper end without any support for the wand. Should the wand be removed in this second mode of operation, the disc because of its aerodynamic configuration which generates a downward force, will descend and spin on the flat surface like a top. A feature of the invention is that both the central depression and the tip of the wand that coacts therewith are provided with low friction surfaces.

United States Patent Farhi et al.

[ July4, 1972 [54] REVERSIBLE AERODYNAMIC DISC AND GYROSCOPIC TOY [72] Inventors: Raphael Farhi; Edward H. Farhi, both of 1744 Monroe Avenue, New York, N.Y. 10457 [22] Filed: June2l,197l

[21] Appl.No.: 154,848

[56] References Cit d the air depending upon the magnitude and direction of the force applied by the wand and the speed of rotation of the UNITED STATES PATENTS disc. With the concave surface of the disc facing upwardly,

1 404 132 1/1922 Manes ..46/47 by f Plug as first emb9dimem 3/1938 W0rSt u "46/47 or by inverting the entire disc as in the second embodiment, a

3:359678 12/1967 Headrick '46/74 R gyroscopic toy is provided. With the disc rotating and with its 3,5451760 l/l968 Wilson ..46/74 D cmcave Surface facmg Pwardly, the end the wand Primary ExaminerLouis G. Mancene Assistant Examiner-Robert F. Cutting 57 ABSTRACT A disc with an aerodynamically shaped concave/convex surface and an inwardly turned rim has a central portion that includes a central circular depression in at least one transverse end surface thereof. The depression has a concave bottom and a right cylindrical side wall. In one embodiment of the invention, the central portion constitutes a readily removable and invertible plug so that the central depression may be arranged to face either inwardly or outwardly of the disc. In an alternative embodiment of the invention, the central portion is made integrally with the concave/convex surface and oppositely facing central depressions are formed on both (inner and outer) transverse end surfaces thereof. The disc is adapted to be spun by twirling an elongated wand the tip of which is in an inwardly or outwardly facing central depression of the disc, the disc being supported by the wand during such twirling. With the concave surface of the disc facing downwardly, twirling of .the wand causes the disc to rotate, and after the disc is turning with sufficient speed a slight push of the wand in an upward direction will cause the disc either to hover or to sail through the tip of which now is in the outwardly and downward facing depression can be placed on a flat surface where it will remain erect with the disc spinning on its upper end without any support for the wand. Should the wand be removed in this second mode of operation, the disc because of its aerodynamic configuration which generates a downward force, will descend and spin on the flat surface like a top. A feature of the invention is that both the central depression and the tip of the wand that coacts therewith are provided with low friction surfaces.

8 Claims, 5 Drawing Figures REVERSIBLE AERODYNAMIC DISC AND GYROSCOPIC TOY BACKGROUND OF THE INVENTION portion (the base of the saucer) that approximates the shape of an airfoil. The cross-sectional configuration of the Frisbee utilizes the well known characteristics of airfoil lift so that when the toy is thrown in a fashion-such that it rotates about its central axis while travelling along a path through the air, it simulates the flight of a flying saucer.

It is also well known that a dish can be set into spinning motion and then supported on a twirling wand. Jugglers frequently use these.

SUMMARY OF THE INVENTION 1 Brief Description of the Invention The present invention is comprised of a concave/convex, aerodynamically shaped rimmed disc having a central plug. In the preferred embodiment of the present invention, the central plug is readily removable and invertible either by threading, or a bayonet type interlock, or any suitablesnap-action arrangement. The central plug is provided with a central circular depression in at least one transverse end face thereof. The depression has a concave bottom and right cylindrical side wall. The toy comprising the present invention may be used as a flying saucer by setting the disc spinning through twirling of a wand having its tip in the depression, the concave surface of the disc and the depression facing downwardly. Thereafter a slight upward push on the wand or withdrawing the wand downwardly will cause the spinning disc to hover or fly. When the central plug is inverted in the preferred embodiment of this invention the disc assumes gyroscopic characteristics and, with the concave surface facing upwardly and the depression facing downwardly, the disc may, through twirling on a wand having its tip in the depression, be set spinning so that the disc will gyroscopically balance on the wand if the lower end thereof is supported on a flat surface. Alternatively, the central plug may be provided with central depressions on both transverse end surfaces and the disc may be used as described hereinabove, either as a flying saucer or as a gyroscopic toy. With the central depressions fon'ned on both transverse end faces the plug preferably is integral with the disc. It is advantageous to provide a coating of a low friction material such as Teflon (polytetrafluoroethylene) on the cooperating surfaces of the wand and the central depression(s).

The disc desirably has its rim thickened to concentrate a large portion of the mass of the toy as far from the axis of rotation as is possible so as to increase the rotational momentum (flywheel effect). As is well known, the rotational momentum, or spin, depends on the mass of the disc, the square of the distance of the individual particles of the mass to the axis or rotation and the speed of rotation or revolutions per minute. When the toy is used as a gyroscope it will continue to spin as long as no external forces act upon the disc or until friction slows the disc to a degree at which it will no longer gyroscopically maintain its horizontal aspect with the wand erect.

2. Purposes of the Invention It is an object of the present invention to provide an improved spinning toy.

It is another object of the present invention to provide an improved spinning toy that combines the characteristics of a flying saucer and a gyroscope.

Still another object of the present invention is to provide an improved spinning toy, as described above, wherein a central plug is provided which permits use of the toy in either of two different modes.

Still another object of the present invention is to provide an improved spinning toy, as described above, wherein the central plug is readily removable and invertible so that the toy can be easily converted between two different modes of use.

A feature of the present invention, as described above, is that the removable central plug is provided with a central depression on at least one transverse end surface thereof for engagement with the tip of a twirling wand.

An additional object of the present invention is to provide an improved spinning toy wherein the central plug is integral with the disc and is provided with central depressions on both transverse end surfaces thereof.

A further object of the present invention is to provide an improved combination spinning toy, as described above, which may be set into rotation by twirling on the tip of a wand, and, thereafter, utilizing theaerodynamic characteristics thereof, fly off of the wand, or, utilizing the gyroscopic characteristics thereof, can be balanced on the wand which is supported erect on a flat surface.

Other objects of the invention will in part be obvious and in part be pointed out hereinafter.

The invention accordingly consists in the features of constructions, combinations of elements, and arrangements of parts which will be exemplified in the toys hereinafter described, and of which the scope of application will be indicated in the appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS In the accompanying drawings, in which are shown two of the possible embodiments of the invention,

FIG. I is a perspective view illustrating the reversible aerodynamic disc/gyroscope disc which is the principal element of the present invention, the same being shown in position for use as an aerodynamic disc;

FIG. 2 is an exploded, sectional elevational view taken substantially along the line 22 of FIG. I, and also showing the wand;

FIG. 3 is a fragmentary central sectional elevational view of the disc in an inverted position with the central plug reversed and facing downwardly, the toy being illustrated in use as a gyroscope;

FIG. 4 is a side view of the disc and wand functioning in a gyroscopic mode; and

FIG. 5 is a fragmentary central sectional elevational view of the disc embodying an alternate form of the invention in which the central plug is in one piece with the disc.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now in detail to the drawings, and in particular to FIGS. 1 and 2, the reference character 10 generally designates the toy comprising the present invention. Said toy includes a saucer-like, concave/convex disc 12 having a base 13. The disc simulates an airfoil in cross section. The periphery of the base I2 is provided with a thickened and inwardly directed rim 14 to complete the airfoil configuration. Centrally of the disc 10 there is provided an axially elongated collar 16 which, in the preferred embodiment of the invention, includes a female thread in its bore 18.

A plug 20 is removably secured in the threaded bore 18 and, on at least one of two axially spaced transverse end faces 22 thereof, there is formed a central circular depression 24 having a concave base 24a and a right cylindrical side wall 24b.

A wand 26 is also used with the toy l0 and is provided with a fitting 28 on its tip. The fitting has a convex top 28a and a right cylindrical side wall 28b. The shape of the fitting is exemplificative of an operative configuration, but is not critical. A ball or discus shapeis acceptable. The parameters are that the fitting be circular in plan, and preferably convex on top. The configuration of the side wall is not important since, as soon will be seen, it merely rides on theside wall of the depression during twirling of the wand. The fitting is adapted to be inserted in the central depression 24 when the depression is facing downwardly. Advantageously, the depression 24 and the fitting 28 are coated with a low friction material such as Teflon (polytetrafluoroethylene) or the like. For the sake of low cost and ease of production the disc 12 and plug 20 are made from a thermoplastic, preferably by injection molding.

When used as an aerodynamic toy the disc 12 is oriented to direct the. concave surface 120 downwardly as shown in FIG. 2. The disc 12 is then balanced on the fitting 28 of the wand 26 with the concave base 240 of the depression resting on the convex top28a of the projection. Then the wand 26 is twirled, causing the fitting 28, and specifically its side wall 28b to ride aroundthe side wall 24b of the depression. This imparts a spinning motion to the disc. When the speed of rotation is sufficiently great the twirling of the wand is stopped whereupon the center of the convex top 28a rides up to the center of the curved base 24a which latter preferably has a slightly greater radius of curvature. than that of the top 28a. Thus the disc spins with a minimum of friction, the walls 24b and 28b being out of contact. Now a slight, upwardly directed force on the wand 26 will cause the disc 12 to fly off utilizing the aerodynamic characteristics of the concave/convex airfoil cross section. If the force is directly upward the disc will hover and if the air currents are suitable, will proceed sidewise. If the force is also lateral the disc will fly like a tossed Frisbee. The flywheel effect of the thickened rim will aid in maintaining the rotational speed of the disc and lengthen the duration and speed of flight. The foregoing constitutes one mode of operation ofthe toy.

When it is desired to use the toy as a gyroscope (the second mode of operation), the plug is unscrewed, inverted and screwed back into the threaded base 18, so that the depression 24 faces outwardly in the same direction as the convex surface 12b. It should be noted at this time that although a threaded coupling is illustrated for releasably attaching the plug 20 to the collar 16, other arrangements may be used such as a bayonet type connection or any snap action, quick disconnect coupling that is well known. For usein the second mode the disc is held upside down with the concave surface 12a facing upwardly, the convex surface l2b.facing downwardly and-the depression 24 facing downwardly as in FIGS. 3 and 4.-Then the toy l0-is balanced on the fitting 28 of the erect wand 26. Because the center of mass of the disc 12 now is above the point support at the fitting 28 the disc is in unstable equilibrium. To prevent the disc from toppling off the fitting, the disc has a spinning motion imparted thereto by manually turning the disc with the wand stationary. The speed of rotation thus engendered need only be enough to stabilize the disc. The user thentwirls the wand rapidly which causes the disc to spin at a high speed by the action heretofore described in connection with the first mode of operation, and thus enables the disc to act as a gyroscope, i.e. the disc will spin atop the wand with its axis of rotation remaining vertical.

The bottom of the wand may be seated on a flat surface 30 with the wand erect and the stabilizing effect of the spinning disc will keep the wand in such position without additional support until the disc slows down. Should the wand 26 be removed the toy 10 will descend slowly and will continue to spin with its transverse end surface 22 on the flat surface 20, like a top.

An alternative embodiment of the present invention is illustrated in FIG. 5. The toy 32 therein disclosed is comprised of a saucer-like disc 34 having a concave surface 34a and a convex surface 34b which in cross section simulates an airfoil. The periphery of the disc is provided with a thickened inwardly directed rim (not shown) the same as the rim 14 of the first form of the invention 36. Centrally of the disc-like portion 34 there is provided an axially elongated integral plug 38 having axially spaced transverse end faces 40 and 42. A central depression 44 is fonned in the transverse end face 40 and another central depression 46, facing in the opposite direction is formed in the transverse end face 42. The depressions 44, 46 have a configuration identical to that of the depression 24. As in the previously described embodiment, the depressions 44, 46 are preferably coated with an anti-friction material such as Teflon.

A wand 26 is used with the embodiment illustrated in FIG. 5 in the same manner as described in connection with the first embodiment, except that the central plug 38, comparable to the plug 20 is not inverted since it is integral with the disc 34. Thus, when converting from an aerodynamic toy with the concave surface 34a facing downwardly to a gyroscopic toy with the concave surface 340 directed upwardly, it is only necessary to invert the entire disc.

From the foregoing it will be evident that an improved toy has been provided that combines the desirable aerodynamic characteristics of an airfoil with those of a gyroscope. The toy may be readily molded from any suitable, rugged plastic material that will withstand frequent use, efg. polyethylene. The first described embodiment of the present invention provides for rapid conversion from one typeof toy to the other merely by removing and inverting a central plug. In the second embodiment of the present invention, the central plug need not be removed since it is integral with the disc and the disc need only be inverted. In both embodiments of the invention the depression formed in at least one transverse end surface of the central plug cooperates with the tip of a wand. When used as an aerodynamic toy the disc is merely spun by twirling the wand and is caused to fly off the wand by the application of a small upward force. When used as a gyroscopic toy the disc is likewise spun by twirling the wand which then is stood upright on a flat surface.

It thus will be seen that there are provided toys which achieve the several objects of the invention and are well adapted to meet the conditions of practical use.

As various possible embodiments might be made of the above invention, and as various changes might be made in the embodiments above set forth, it is to be understood that all matter herein described, or I shown in the accompanying drawings, is to be interpreted as illustrative and not ina limiting sense.

Having now described the invention, there is claimed as new and desired to' be secured by Letters Patent:

1. A reversible, aerodynamic and gyroscopic toy comprisa. a concave/convex disc with a peripheral rim;

b. a central boss formed on said disc, said boss including a plug defined by two axially spaced, transverse end surfaces;

c. a central circular depression formed in at least one of said transverse end surfaces of said plug said plug being structured to dispose a depression in downwardly facing orientations regardless of whether the concave or convex surface of the disc faces upwardly; and

d. an elongated wand having a circular tip that is receivable in said depression so that by twirling the wand the disc can be spun.

2. A toy in accordance with claim 1 wherein said plug is removable and wherein means is provided for releasably retaining said plug in said disc whereby when said toy is used aerodynamically said depression in said plug and said concave surface of said disc face downwardly and when said toy is used gyroscopically said plug is removed and inverted so that said depression therein still faces downwardly and said concave surface of said disc faces upwardly 3. A toy in accordance with claim 2 wherein said retaining means comprises mating screw threads.

4. A toy in accordance with claim 1 wherein the coacting surfaces of said depressionand said wand are coated with a low-friction material.

5. A toy in accordance with claim 1 wherein said disc and said plug are integral and a depression is formed in both axially spaced transverse end surfaces of said plug.

6. A toy in accordance with claim 5 wherein the coacting surfaces of said plug and said wand are coated with a low-friction material.

7. A toy in accordance with claim 1 wherein the depression has a concave base and a right cylindrical side wall and wherein the top of the wand has a convex top.

8. A toy as set forth in claim 7 wherein the radius of curvature of the base of the depression is greater than the radius of curvature of the top of the wand. 

1. A reversible, aerodynamic and gyroscopic toy comprising: a. a concave/convex disc with a peripheral rim; b. a central boss formed on said disc, said boss including a plug defined by two axially spaced, transverse end surfaces; c. a central circular depression formed in at least one of said transverse end surfaces of said plug said plug being structured to dispose a depression in downwardly facing orientations regardless of whether the concave or convex surface of the disc faces upwardly; and d. an elongated wand having a circular tip that is receivable in said depression so that by twirling the wand the disc can be spun.
 2. A toy in accordance with claim 1 wherein said plug is removable and wherein means is provided for releasably retaining said plug in said disc whereby when said toy is used aerodynamically said depression in said plug and said concave surface of said disc face downwardly and when said toy is used gyroscopically said plug is removed and inverted so that said depression therein still faces downwardly and said concave surface of said disc faces upwardly
 3. A toy in accordance with claim 2 wherein said retaining means comprises mating screw threads.
 4. A toy in accordance with claim 1 wherein the coacting surfaces of said depression and said wand are coated with a low-friction material.
 5. A toy in accordance with claim 1 wherein said disc and said plug are integral and a depression is formed in both axially spaced transverse end surfaces of said plug.
 6. A toy in accordance with claim 5 wherein the coacting surfaces of said plug and said wand are coated with a low-friction material.
 7. A toy in accordance with claim 1 wherein the depression has a concave base and a right cylindrical side wall and wherein the top of the wand has a convex top.
 8. A toy as set forth in claim 7 wherein the radius of curvature of the base of the depression is greater than the radius of curvature of the top of the wand. 